The invention relates to cutting devices, and more particularly to devices for stripping or cutting the insulation or dielectric material which surrounds the inner metallic conductor within a cable or wire.
Presently, there is a significant demand for scrap copper and other metals which may be recycled and formed into other desirable products. One widely available source for scrap metal is contained in scraps of cable which, for a variety of reasons, are no longer useful. For example, a large number of pieces of copper wire are typically left over after wiring a house for high and low voltage transmission throughout the house.
If the metal conductor in the scrap cable is to be recycled, the insulation or dielectric material that surrounds the inner metallic conductor must be removed. In addition, many salvage yards require the insulation to be stripped from the conductor before it will be accepted for recycling. In order to strip the insulation from the metallic conductor, a wire stripping tool is typically employed. The wire stripping tools that are presently known for accomplishing this task range from sophisticated complicated machinery to simple hand tools.
A common element in most wire stripping devices is the blade that is necessary to split the insulation on the cable. However, these tools are often undesirable for quick and easy removal of vast amounts of insulation housing from large volumes of cable. For example, if sophisticated machinery is used to remove the insulation from the cable, the procedure tends to be expensive. The expense of this sophisticated machinery can also prevent their use in the field since such expense offsets the profit which can be obtained from the recycling process.
A further example of problems that arise is when hand tools are used to strip wire. Existing hand tools for stripping wire do not allow for a quick removal of the housing from the cable because precise adjustments that account for wire diameter and length must be made prior to removing the housing from a particular cable. Thus, a non-desirable amount of time may be required to remove the cable insulation.
Another disadvantage of using hand tools for removing insulation with large amounts of cable is safety. Safety is compromised when the user must manipulate a bladed hand tool in one hand and a cable in the other hand. This scenario requires significant coordination and thus, may be unsafe even for highly skilled users. a cable stripping tool is needed that is inexpensive, easy to operate, safe, and designed to quickly strip the insulation housing from large amounts of cable.
In accordance with the invention, a device is disclosed for stripping the insulation or dielectric housing from a cable or wire. The cable stripping device includes a wire guide block having a bore extending transversely therethrough and a slot which extends from one end or side of the block to the bore and a knife which is pivotable between an unengaged position to an engaged position. In the engaged position, the blade extends through the slot and extends at least partially into the bore to engage with the cable or wire located within the bore, whereby the knife is positioned to cut the insulation or dielectric housing from the cable or wire as the cable or wire is pulled through the bore.
In one aspect of the invention, the knife is a rotary knife.
In another aspect of the invention, the wire guide block includes a second bore that a different diameter, either smaller or larger, than the diameter of the first bore for accommodating and receiving a differently sized cable or wire.
The device may include an elongated holder for receiving the wire guide block within a hollow portion of the holder. A biasing device, such as a coil spring located within the hollow portion of the elongated holder, may be provided for biasing the wire guide block outwardly from the elongated holder. A travel limiting device may also be provided for limiting the extent of outward travel of wire guide block biased by the biasing device. The biasing device serves to facilitate engagement of the knife with the cable or wire within the bore.
In one aspect of the invention, the travel limiting device comprises a channel formed in either the wire guide block or the elongated holder and a set screw is located on the other part such that the set screw cooperates with the channel to limit the travel of the wire guide block within the hollow portion of the holder.
In one preferred embodiment the knife is pivotably disposed on a linkage assembly connected to the holder. The linkage assembly may include a clevis attached to the holder and a knife arm pivotably attached to the clevis at one of its end. The other end of the knife arm holds the knife blade and permits it to pivot into the bore.
In one form of the invention, a handle connected to the knife arm may be provided for increasing the leverage of a user to facilitate pivoting the knife arm between the unengaged and engaged positions. A knife guard located in proximity to the knife may also be provided for shielding the knife from the user.
In another aspect of the invention, a latching device may be provided for locking the knife in the engaged position. The latching device may include a latch having a detent. A rounded protrusion located on the device, such as on the clevis of holder, may also be provided to cooperate with the detent portion of the latch to engaged the detent to lock the knife arm in the engaged position. The latch may also include a camming surface which engages with the rounded to facilitate the engagement of the protrusion with the latch and to guide the protrusion into the detent.
It is therefore an object of the present invention to provide a device that facilitates cutting the insulation or dielectric housing surrounding the inner conductor of a cable or wire to facilitate the stripping the insulation from the metallic conductor to facilitate recycling of the conductor and disposal of the insulation.
Other objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description, together with the drawings and the appended claims.